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[Chris Kay <address@concealed>]

I see in the Sympa requirements docs that “Inbound and outbound SMTP connections (typically on TCP port 25) should be allowed”, but my security team told me that we must use 587 since 25 is insecure. Do I have to allow port 25 traffic to the server for Sympa to function?

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From: address@concealed <address@concealed> on behalf of Janky Jay, III <address@concealed>
Sent: Saturday, June 8, 2024 1:03 AM
To: address@concealed <address@concealed>
Subject: Re: [en@sympa] Using Port 587 instead of 25 for Postfix under RHEL

 

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Hi Chris, Port 587 should be a Postfix setting (submissions,) not a Sympa setting. This will limit receiving email from external servers, though, as most use SMTP(S) (port 25) for delivery. I'd suggest using SMTP(S) on ports 25 (via STARTTLS)

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Hi Chris,

Port 587 should be a Postfix setting (submissions,) not a Sympa setting. This will limit receiving email from external servers, though, as most use SMTP(S) (port 25) for delivery. I'd suggest using SMTP(S) on ports 25 (via STARTTLS) alongside submissions (587) for the most acceptable configuration.

That being said, maybe I'm misunderstanding your question? Are you looking for something else more specific to Sympa? Like, restricting Sympa to only deliver via submissions? (Sympa will never receive anything from the submissions port as it would be handed off to the LDA or LMTP.)

Regards,
Janky Jay, III

On June 7, 2024 10:01:30 PM UTC, Chris Kay <address@concealed> wrote:

New admin installing Sympa for the first time. I have everything installed, but I’m having a heck of time trying to set up Sympa to use send/receive over 587 only, and my research has found conflicting suggestions.

 

Can someone share how they accomplished this please?

 

Thanks and TGIF!